204 ENGLISH BOTANY. 
wing gradually increasing in width from a little above the base 
(where it commences insensibly) to the apex; style short, not half 
as long as the apical lobes of the wing. Seeds 38 to 6 in each cell 
of the pod, ovoid, sub-compressed, without concentric ridges. 
In stony ground. Extremely local, being apparently confined 
to Oxfordshire and Gloucestershire. It occurs near Burford in the 
former county, and Bourton-on-the-Water, Naunton, Sapperton 
Tunnel, near Cirencester, and a few other places in the latter. 
England. Annual or Biennial. Spring. 
Stem erect, simple or branched at the base, 2 to 9 inches high. 
Radical leaves in a rosette, spatulate, with a roundish oval or 
ovate lamina abruptly contracted into a footstalk; stem leaves 
few, ovate or lanceolate-ovate, cordate, amplexicaul, with rounded 
contiguous lobes at the base; all entire or denticulate. Flowers 
white, 74 inch across. Petals nearly twice as long as the sepals, 
oblong, oblanceolate, entire, and rounded at the apex. Fruiting 
raceme rather short, about equal in length to the rest of the stem. 
Fruit pedicels spreading horizontally, $ to 4 inch long. Pods 
flattish above, convex below, % to + inchlong, and nearly as broad 
as long at the top including the wing, or exclusive of it ¢ to § inch 
long, and were it not winged the shape would be shortly roundish 
obovate; the wing with a stout marginal nerve running round the 
edge. Seeds pale orange-brown, finely punctured. Whole plant 
glabrous and glaucous. 
This species is readily distinguished from the others of this 
genus by the large rounded approximate auricles of the stem leaves. 
T. erraticum (Jord. Pug. Plant. Nov. p. 12) appears to be 
scarcely entitled to be ranked asa sub-species. ‘The Gloucestershire 
plant is intermediate between specimens of T. perfoliatum and 
T. erraticum (C. Martin, Pl. de Lyon), having the pod of the 
former, the leaves and seeds of the latter form. 
Perfoliate Penny Cress, Perfoliate-leaved Bastard Cress, 
Perfoliate Shepherd's Purse. 
| French, Zabouret Perfolié. 
SPECIES I1.—THLASPI ALPESTRE. Linn. 
Puates CXLVI. CXLVII. CXLVIII. 
Rootstock slender, branched, woody, or none. Stem leaves 
cordate-sagittate at the base. Pods (including the wing) oblong- 
obovate, narrowed at the base, more or less deeply retuse at the 
apex; wing gradually increasing in breadth from the base, where it 
